radiator bleed valve problem

[Fred]

Hi,

I have noticed a trend for new radiators to be supplied with metal and plastic bleed valves that protrude from the radiator. They look ugly (imho, ymmv, etc), but one advantage is that they have a hexagon faces, which allow you to grab them with a spanner or socket set.

The radiators here have those brass bleed valves that screw in flush with the radiator. They are much prettier but I see now that having nothing to grab hold of is a disadvantage. I had one that was weeping slightly. It's my fault, didn't get round to fixing it straight away, so in the meantime it has rusted the radiator around it. Actually the rust has solved the problem by sealing the gap it was weeping through but I didn't think of that at the time!

I thought I would remove the valve with a square-ended radiator spanner and replace it with one of the ugly ones (which, as another benefit, has a rubber seal around them).

The problem is that the valve was so rusted in place that the spanner turned but the valve did not. It rounded the spanner and the square recess in the valve!

I had read on a car group about "plus gas". It sounded useful, so I bought one "just in case". So I thought I now had an opportunity to use it. I let it soak in and tried to use a left-handed drill but the valve still did not turn. Perhaps the brass is too soft to be drilled? Now I've got a valve with a hole in, so I can't refill the radiator!

Any other ideas what to do next? I don't fancy heating with a blow torch for fear of destroying the paint on the radiator (it's whatever enamel finish it leaves the factory with).

Short of bodging it and filling the hole with epoxy putty, any ideas what to try next?

TIA

[Moonraker]

I had a radiator whose valve was stuck solid. In the end I took it to a local metal work company and they sealed it completely and welded in a new one.

[Fred]

Thanks for a fast reply! What type of company would I look for in the yellow pages?

This is the kind of valve, if I didn't describe it very well earlier:

[NT]

screw can be nothing more than a ss screw in the right size threaded hole.

NT

[Phil L]

New radiators are quite cheap, why not price one up, it'll probably work out cheaper than taking the rusty old one off to be repaired. What size is it?

[Lobster]

Makes sense to me if you can't diy the repair... furthermore, I'd have thought that a rad suffering from a rust-related issues is likely to be near the end of its life anyway? I speak as someone who has twice had rads panels burst (mid-panel-pinholes). Not pretty... :(

[Harry Bloomfield]

Organise a slightly tapered lump of steel (a bench grinder is useful) which can be hammered into the socket, along with some means of turning it. Get the end red hot and hammer it tightly into the socket. The heat should heat up the valve body and free it off, just wait until it cools and tap it in a bit further - you will then likely be able to undo it without much effort and no damage to the paint.

[newshound]

That's what I would do, and put a new bleed valve (pattern of your choice)in the other end.

[Grimly Curmudgeon]

fit a replacement.

[Fred]

Thank you everyone for all your help.

The only rust is around the bleed valve. I don't think the radiator is that old; perhaps 5-6 years? It's a fairly standard 600mm high panel radiator, just over a metre long. About £60 to replace from the likes of toolstation. So it's not as expensive to replace as a designer radiator but I don't like the throw-away society if I can make do and mend ;)

[Fred]

Yes, I was surprised at that. It's one of these:

So you now have a insert with a large hole through it. Not having a

What would you use to cut the slot: a multi tool, or something else that I have not thought of?

TIA

[Fred]

I haven't done anything like this before. What do I do? Drill a hole slightly smaller than the width across the threads, that way I remove the bulk of the fitting but do not damage the threads on the radiator? Do you know what size drill I would need? I think it may be 19mm.

That sounds straightforward but how do I then remove the remains of the brass threads from the radiator ones?

Luckily it's got warmer and I don't need the heating on!

TIA

[Dave Liquorice]

Don't think you'd get a multitool or a dremmel in, though I suppose a burr might work rather than a blade. I'd drill out the bleed hole to allow a junior hacksaw blade in and use that either with a proper pad saw handle or wrap the end in tape to stop it hacksawing your fingers.

[Fred]

Thanks. The smallest multitool blade I have seen is 20mm, which is probably one millimetre too long, though there could be shorter ones out there; I've only had a quick look. I have never seen a dremmel so I wasn't sure how big they were.

Some times only a hand tool will do; the trusty hacksaw blade it will be then.

Thanks.

[Fred]

The problem is it is much easier to measure the outside diameter of the female thread than the inside one; that's why I'm not sure whether it is 18mm or 19mm. Like you suggest, perhaps go for the 18mm bit to allow for wander.

Thanks.

[Fred]

As much as we champion the angle grinder in this group, the junior hacksaw must come a close second, mustn't it?

The lack of a handle is a problem. I was thinking it is a shame that there is not a junior version of this:

having measured the width of a "normal" hacksaw blade, I found it is 13mm, which is small enough in this situation, so this may be the tool to use.

Thanks.

[Fred]

Thanks to all the help I've had here, I have completed the job. Thanks everyone.

I bought a 16mm blacksmiths drill bit from tool station (I also bought a 18mm one but wasn't brave enough to use it).

A close quarter hacksaw with full-size blade was only 13mm wide (IIRC), so the 16mm hole was sufficient to allow the blade in. Is "close quarter hacksaw" an official name? I've only seen it used by tool station; everyone else seems to call it a mini hacksaw, which is a bit vague.

I cut the brass with the hacksaw. It seems I was nervous and didn't go all the way through the brass, but I went far enough to weaken it.

I didn't want to destroy a screwdriver poking it, so found a small cold chisel. I didn't have a chisel with a pointed end, I'll have to get one for next time. The cold chisel was 19mm which knocked the brass out. I think it may have been fractionally too wide and fouled the radiator threads slightly but I screwed a new valve on and it is not leaking (I did the test with the radiator in the garden filled from a hose pipe (am I allowed to say that?)).

I flushed the radiator a few times just to make sure there was no brass swarf inside. I was concerned that some rust flakes were flushed out. I didn't think the radiator was particularly old and I've always added inhibitor to the system. I have a magna clean-like device but that has never seemed to have anything in it. At least there was no sludge. So time will tell whether there are more problems ahead with this radiator.

Thanks again for your help.